Question

4^x+3+4^x=1040

 

Answer 1

4^{x + 3} + 4^x = 1040

4^x . 4³ + 4^x . 1 = 1040

4^x ( 4³ + 1 ) = 1040

4^x . 65 = 1040

4^x = 1040 : 65 = 16 = 4²

Vậy x = 2

Answer 2

\(4^{x+3}+4^x=1040\)

\(\Leftrightarrow4^x\left(1+4^3\right)=1040\)

\(\Leftrightarrow4^x.65=1040\)

\(\Leftrightarrow4^x=16\)

\(\Leftrightarrow x=2\)